SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '294b8927e50bcbb224840cccebbc070d65bc378bfd67f6d807311bfe2f9cf673' 
  AND token = '288JjyX2u0w/e7KIcaLavL7E5b47ceTPRTHLmqq7sok=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}